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1.
Cell ; 162(1): 33-44, 2015 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-26140591

RESUMO

SNPs affecting disease risk often reside in non-coding genomic regions. Here, we show that SNPs are highly enriched at mouse strain-selective adipose tissue binding sites for PPARγ, a nuclear receptor for anti-diabetic drugs. Many such SNPs alter binding motifs for PPARγ or cooperating factors and functionally regulate nearby genes whose expression is strain selective and imbalanced in heterozygous F1 mice. Moreover, genetically determined binding of PPARγ accounts for mouse strain-specific transcriptional effects of TZD drugs, providing proof of concept for personalized medicine related to nuclear receptor genomic occupancy. In human fat, motif-altering SNPs cause differential PPARγ binding, provide a molecular mechanism for some expression quantitative trait loci, and are risk factors for dysmetabolic traits in genome-wide association studies. One PPARγ motif-altering SNP is associated with HDL levels and other metabolic syndrome parameters. Thus, natural genetic variation in PPARγ genomic occupancy determines individual disease risk and drug response.


Assuntos
Hipoglicemiantes/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Polimorfismo de Nucleotídeo Único , Tecido Adiposo , Animais , Expressão Gênica , Humanos , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Fatores de Transcrição/metabolismo
2.
Nature ; 600(7890): 647-652, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34937899

RESUMO

Spin-ordered electronic states in hydrogen-terminated zigzag nanographene give rise to magnetic quantum phenomena1,2 that have sparked renewed interest in carbon-based spintronics3,4. Zigzag graphene nanoribbons (ZGNRs)-quasi one-dimensional semiconducting strips of graphene bounded by parallel zigzag edges-host intrinsic electronic edge states that are ferromagnetically ordered along the edges of the ribbon and antiferromagnetically coupled across its width1,2,5. Despite recent advances in the bottom-up synthesis of GNRs featuring symmetry protected topological phases6-8 and even metallic zero mode bands9, the unique magnetic edge structure of ZGNRs has long been obscured from direct observation by a strong hybridization of the zigzag edge states with the surface states of the underlying support10-15. Here, we present a general technique to thermodynamically stabilize and electronically decouple the highly reactive spin-polarized edge states by introducing a superlattice of substitutional N-atom dopants along the edges of a ZGNR. First-principles GW calculations and scanning tunnelling spectroscopy reveal a giant spin splitting of low-lying nitrogen lone-pair flat bands by an exchange field (~850 tesla) induced by the ferromagnetically ordered edge states of ZGNRs. Our findings directly corroborate the nature of the predicted emergent magnetic order in ZGNRs and provide a robust platform for their exploration and functional integration into nanoscale sensing and logic devices15-21.

3.
Proc Natl Acad Sci U S A ; 120(49): e2314857120, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38019855

RESUMO

The suprachiasmatic nucleus (SCN) of the hypothalamus is the site of a central circadian clock that orchestrates overt rhythms of physiology and behavior. Circadian timekeeping requires intercellular communication among SCN neurons, and multiple signaling pathways contribute to SCN network coupling. Gamma-aminobutyric acid (GABA) is produced by virtually all SCN neurons, and previous work demonstrates that this transmitter regulates coupling in the adult SCN but is not essential for the nucleus to sustain overt circadian rhythms. Here, we show that the deletion of the gene that codes for the GABA vesicular transporter Vgat from neuromedin-S (NMS)+ neurons-a subset of neurons critical for SCN function-causes arrhythmia of locomotor activity and sleep. Further, NMS-Vgat deletion impairs intrinsic clock gene rhythms in SCN explants cultured ex vivo. Although vasoactive intestinal polypeptide (VIP) is critical for SCN function, Vgat deletion from VIP-expressing neurons did not lead to circadian arrhythmia in locomotor activity rhythms. Likewise, adult SCN-specific deletion of Vgat led to mild impairment of behavioral rhythms. Our results suggest that while the removal of GABA release from the adult SCN does not affect the pacemaker's ability to sustain overt circadian rhythms, its removal from a critical subset of neurons within the SCN throughout development removes the nucleus ability to sustain circadian rhythms. Our findings support a model in which SCN GABA release is critical for the developmental establishment of intercellular network properties that define the SCN as a central pacemaker.


Assuntos
Relógios Circadianos , Ritmo Circadiano , Humanos , Ritmo Circadiano/fisiologia , Neurônios/metabolismo , Relógios Circadianos/fisiologia , Peptídeo Intestinal Vasoativo/genética , Peptídeo Intestinal Vasoativo/metabolismo , Núcleo Supraquiasmático/metabolismo , Ácido gama-Aminobutírico/metabolismo , Arritmias Cardíacas/metabolismo
4.
Cell ; 142(4): 515-6, 2010 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-20723752

RESUMO

The mechanism by which voltage-dependent ion channels sense membrane potentials has been the most intensively studied and debated topic in modern ion channel research. In this issue, Xu et al. (2010) provide new insights into the minimal topological and physicochemical features required for voltage sensing.

5.
Nature ; 569(7758): 723-728, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31043742

RESUMO

High-grade serous carcinoma has a poor prognosis, owing primarily to its early dissemination throughout the abdominal cavity. Genomic and proteomic approaches have provided snapshots of the proteogenomics of ovarian cancer1,2, but a systematic examination of both the tumour and stromal compartments is critical in understanding ovarian cancer metastasis. Here we develop a label-free proteomic workflow to analyse as few as 5,000 formalin-fixed, paraffin-embedded cells microdissected from each compartment. The tumour proteome was stable during progression from in situ lesions to metastatic disease; however, the metastasis-associated stroma was characterized by a highly conserved proteomic signature, prominently including the methyltransferase nicotinamide N-methyltransferase (NNMT) and several of the proteins that it regulates. Stromal NNMT expression was necessary and sufficient for functional aspects of the cancer-associated fibroblast (CAF) phenotype, including the expression of CAF markers and the secretion of cytokines and oncogenic extracellular matrix. Stromal NNMT expression supported ovarian cancer migration, proliferation and in vivo growth and metastasis. Expression of NNMT in CAFs led to depletion of S-adenosyl methionine and reduction in histone methylation associated with widespread gene expression changes in the tumour stroma. This work supports the use of ultra-low-input proteomics to identify candidate drivers of disease phenotypes. NNMT is a central, metabolic regulator of CAF differentiation and cancer progression in the stroma that may be therapeutically targeted.


Assuntos
Fibroblastos Associados a Câncer/metabolismo , Nicotinamida N-Metiltransferase/metabolismo , Proteômica , Fibroblastos Associados a Câncer/enzimologia , Linhagem Celular Tumoral , Células Cultivadas , Metilação de DNA , Progressão da Doença , Feminino , Histonas/química , Histonas/metabolismo , Humanos , Metástase Neoplásica , Niacinamida/análogos & derivados , Niacinamida/metabolismo , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Fenótipo , Prognóstico , S-Adenosil-Homocisteína/metabolismo , S-Adenosilmetionina/metabolismo
6.
Mol Cell ; 65(2): 260-271, 2017 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-28107648

RESUMO

Poly(ADP-ribosyl)ation (PARylation) is a post-translational modification of proteins mediated by PARP family members, such as PARP-1. Although PARylation has been studied extensively, few examples of definitive biological roles for site-specific PARylation have been reported. Here we show that C/EBPß, a key pro-adipogenic transcription factor, is PARylated by PARP-1 on three amino acids in a conserved regulatory domain. PARylation at these sites inhibits C/EBPß's DNA binding and transcriptional activities and attenuates adipogenesis in various genetic and cell-based models. Interestingly, PARP-1 catalytic activity drops precipitously during the first 48 hr of differentiation, corresponding to a release of C/EBPß from PARylation-mediated inhibition. This promotes the binding of C/EBPß at enhancers controlling the expression of adipogenic target genes and continued differentiation. Depletion or chemical inhibition of PARP-1, or mutation of the PARylation sites on C/EBPß, enhances these early adipogenic events. Collectively, our results provide a clear example of how site-specific PARylation drives biological outcomes.


Assuntos
Adipócitos/enzimologia , Adipogenia , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Células-Tronco Embrionárias/enzimologia , Poli(ADP-Ribose) Polimerase-1/metabolismo , Poli Adenosina Difosfato Ribose/metabolismo , Processamento de Proteína Pós-Traducional , Transcrição Gênica , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Animais , Sítios de Ligação , Proteína beta Intensificadora de Ligação a CCAAT/genética , DNA/genética , DNA/metabolismo , Células-Tronco Embrionárias/efeitos dos fármacos , Genótipo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação , Células NIH 3T3 , Fenótipo , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Poli(ADP-Ribose) Polimerase-1/deficiência , Poli(ADP-Ribose) Polimerase-1/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Ligação Proteica , Domínios Proteicos , Interferência de RNA , Transdução de Sinais , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos , Ativação Transcricional , Transfecção
7.
Nano Lett ; 24(17): 5387-5392, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38629638

RESUMO

Topological phases in laterally confined low-dimensional nanographenes have emerged as versatile design tools that can imbue otherwise unremarkable materials with exotic band structures ranging from topological semiconductors and quantum dots to intrinsically metallic bands. The periodic boundary conditions that define the topology of a given lattice have thus far prevented the translation of this technology to the quasi-zero-dimensional (0D) domain of small molecular structures. Here, we describe the synthesis of a polycyclic aromatic hydrocarbon (PAH) featuring two localized zero modes (ZMs) formed by the topological junction interface between a trivial and nontrivial phase within a single molecule. First-principles density functional theory calculations predict a strong hybridization between adjacent ZMs that gives rise to an exceptionally small HOMO-LUMO gap. Scanning tunneling microscopy and spectroscopy corroborate the molecular structure of 9/7/9-double quantum dots and reveal an experimental quasiparticle gap of 0.16 eV, corresponding to a carbon-based small molecule long-wavelength infrared (LWIR) absorber.

8.
Semin Cell Dev Biol ; 126: 3-14, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34092510

RESUMO

Nearly all mammals display robust daily rhythms of physiology and behavior. These approximately 24-h cycles, known as circadian rhythms, are driven by a master clock in the suprachiasmatic nucleus (SCN) of the hypothalamus and affect biological processes ranging from metabolism to immune function. Perhaps the most overt output of the circadian clock is the sleep-wake cycle, the integrity of which is critical for health and homeostasis of the organism. In this review, we summarize our current understanding of the circadian regulation of sleep. We discuss the neural circuitry and molecular mechanisms underlying daily sleep timing, and the trajectory of circadian regulation of sleep across development. We conclude by proposing future research priorities for the field that will significantly advance our mechanistic understanding of the circadian regulation of sleep.


Assuntos
Relógios Circadianos , Animais , Relógios Circadianos/fisiologia , Ritmo Circadiano/fisiologia , Mamíferos , Sono/fisiologia , Núcleo Supraquiasmático/fisiologia
9.
J Am Chem Soc ; 146(27): 18730-18742, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38943684

RESUMO

Nanoparticles of high-entropy materials that incorporate five or more elements randomized on a crystalline lattice often exhibit synergistic properties that can be influenced by both the identity and number of elements combined. These considerations are especially important for structurally and compositionally complex materials such as multimetal multianion compounds, where cation and anion mixing can influence properties in competitive and contradictory ways. Here, we demonstrate the synthesis of a large library of colloidal high-entropy rare earth oxyhalide (REOX) nanoparticles. We begin with the synthesis of (LaCePrNdSmEuGdDyHoErYbScY)OCl, which homogeneously incorporates 13 distinct rare earth elements. Through time point studies, we find that (LaNdSmGdDy)OCl, a 5-metal analogue, forms through in situ generation of compositionally segregated core@shell@shell intermediates that convert to homogeneously mixed products through apparent core-shell interdiffusion. Assuming that all possible combinations of 5 through 13 rare earth metals are synthetically accessible, we propose the existence of a 7099-member REOCl nanoparticle library, of which we synthesize and characterize 40 distinct members. We experimentally validate the incorporation of a large number of rare earth elements using energy dispersive X-ray spectra, despite closely spaced and overlapping X-ray energy lines, using several fingerprint matching strategies to uniquely correlate experimental and simulated spectra. We confirm homogeneous mixing by analyzing elemental distributions in high-entropy nanoparticles versus physical mixtures of their constituent compounds. Finally, we characterize the band gaps of the 5- and 13-metal REOCl nanoparticles and find a significantly narrowed band gap, relative to the constituent REOCl phases, in (LaCePrNdSmEuGdDyHoErYbScY)OCl but not in (LaNdSmGdDy)OCl.

10.
J Am Chem Soc ; 146(28): 19521-19536, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38970561

RESUMO

The seeded growth of one type of nanoparticle on the surface of another is foundational to synthesizing many multifunctional nanostructures. High-entropy nanoparticles that randomly incorporate five or more elements offer enhanced properties due to synergistic interactions. Incorporating high-entropy nanoparticles into seeded growth platforms is essential for merging their unique properties with the functional enhancements that arise from particle-particle interactions. However, the complex compositions of high-entropy materials complicate the seeded growth process due to competing particle growth and chemical reactivity pathways. Here, we design and synthesize a 36-member nanoparticle library to identify and disentangle these competitive interactions, ultimately defining chemical characteristics that underpin the seeded growth of high-entropy alloys on high-entropy metal sulfide nanoparticles. As a model system, we focus on (Cu,Zn,Co,In,Ga)S-SnPdPtRhIr, which combines a high-entropy metal sulfide semiconductor with a high-entropy alloy catalyst. We study the seeded growth of all possible pairwise combinations of Sn, Pd, Pt, Rh, Ir, and SnPdPtRhIr on the metal sulfides Cu1.8S, ZnS, Co9S8, CuInS2, CuGaS2, and (Cu,Zn,Co,In,Ga)S, which have comparable morphologies and sizes. Through these studies, we uncover unexpected chemical reactivities, including cation exchange, redox reactions, and diffusion. Reaction temperature, threshold reduction potentials, metal/sulfide chemical reactivity, and the relative strengths of the various bonds that could be formed during particle growth emerge as the primary factors that underpin seeded growth. Finally, we disentangle these competitive and synergistic chemical reactivities to generate a reactivity map that provides practical guidelines for achieving seeded growth in compositionally complex systems.

11.
Acc Chem Res ; 56(23): 3515-3524, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37992288

RESUMO

Conspectus"Synthesis by design" is often considered to be the primary goal of chemists who make molecules and materials. Synthetic chemists usually have in mind a target they want to make, and they want to be able to design a pathway that can get them to that target as quickly and efficiently as possible. Chemists who synthesize refractory solids, which have melting points above 1000 °C and are often chemically inert at these high temperatures, have access to only a small number of synthetic strategies due to the need to overcome solid-state diffusion, which is the rate-limiting step in such reactions. The use of extremely high temperatures to facilitate diffusion among two or more refractory solids, which precedes any chemical reaction that must occur, generally drives the system to form only the product that is the most thermodynamically stable-the global minimum on an energy landscape-for a certain combination of elements. When trying to target a different product in the same system, one generally cannot rely on thermally driven reactions. Lower-temperature reactions that side step this diffusion limitation can succeed where high temperatures fail by providing access to local minima on an energy landscape. These local minima represent metastable phases that are primed for synthesis, but only if an appropriate pathway and set of reactions can be identified. It is therefore important to develop and understand low-temperature, or "soft", chemical reactions in "hard" refractory systems. These reactions allow us to apply the retrosynthetic framework that molecular chemists rely on to systems where chemists have not previously had such control over reactions, reactivities, and metastable product formation.In this Account, we discuss the development of soft chemical reactions of hard materials in the context of a class of layered, refractory metal borides that are precursors to an emerging family of two-dimensional nanomaterials. Layered ternary metal boride phases such as MoAlB have layers of metal borides, which are chemically unreactive, interleaved with layers of aluminum, which are reactive. Some of the interlayer aluminum can be deintercalated at room temperature in dilute aqueous sodium hydroxide, transforming stable MoAlB into destabilized MoAl1-xB. Mild thermal treatment of submicrometer grains of this destabilized MoAl1-xB sample allows it to traverse the energy landscape and crystallize as Mo2AlB2, a metastable compound. Further thermal treatment transforms Mo2AlB2 into a Mo2AlB2-alumina nanolaminate and ultimately mesoporous MoB, all through continued traversing of the energy landscape using mild chemical and thermal treatments. Similar topochemical manipulations, which maintain structure but change composition, are emerging for other MAB phases and are opening the door to new types of metastable compounds and nanostructured materials in traditionally refractory systems.

12.
Gastrointest Endosc ; 99(4): 490-498.e10, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37871847

RESUMO

BACKGROUND AND AIMS: Peroral endoscopic myotomy (POEM) is a minimally invasive technique used to treat esophageal motility disorders. Opioid use has been demonstrated to adversely affect esophageal dysmotility and is associated with an increased prevalence of esophageal motility disorders. Our aim was to investigate the effect of narcotic use on success rates in patients undergoing POEM. METHODS: This was a single-center, retrospective study of patients undergoing POEM between February 2017 and September 2021. Primary outcomes were post-POEM Eckardt score (ES), distensibility index, and length of procedure. Secondary outcomes included technical success, myotomy length, length of stay, adverse events, reintervention rates, and postprocedure GERD. RESULTS: During the study period, 90 patients underwent POEM for treatment of esophageal dysmotility disorders. Age, sex, race, indications for POEM, and body mass index were not significant between those with or without narcotic use. There were no differences in procedure time, preprocedure ESs, or length of stay. Postprocedure ESs were higher in the group with active narcotic use compared to the group with no prior history (2.73 vs 1.2, P = .004). Distensibility indexes measured with EndoFLIP (Medtronic, Minneapolis, Minn, USA) were not different in patients using narcotics compared with opioid-naïve patients. CONCLUSION: Active narcotic use negatively affects symptom improvement after POEM for the treatment of esophageal motility disorders.


Assuntos
Acalasia Esofágica , Transtornos da Motilidade Esofágica , Miotomia , Cirurgia Endoscópica por Orifício Natural , Humanos , Acalasia Esofágica/etiologia , Estudos Retrospectivos , Analgésicos Opioides/uso terapêutico , Resultado do Tratamento , Transtornos da Motilidade Esofágica/cirurgia , Transtornos da Motilidade Esofágica/etiologia , Miotomia/métodos , Cirurgia Endoscópica por Orifício Natural/efeitos adversos , Esfíncter Esofágico Inferior/cirurgia
13.
J Clin Gastroenterol ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39042493

RESUMO

OBJECTIVE: Endoscopic retrograde cholangiopancreatography (ERCP) may be unsuccessful in patients with duodenal stenosis or malignant ampullary infiltration. Endoscopic ultrasound-guided biliary drainage (EUS-BD) has been proposed as an alternative. We aimed to assess the efficacy and safety of EUS-BD for malignant distal bile duct obstruction using the newly introduced smaller caliber 6 or 8 mm cautery-enhanced lumen-apposing metal stent. METHODS: A multicenter retrospective study was performed on patients with unresectable malignant distal bile duct obstruction who underwent EUS-BD between 2021 and 2022 after unsuccessful ERCP. RESULTS: Thirty-two patients were included [7 (53.13%) males], with a mean age of 72.2 ± 12.5 years. The technical success rate was 100%. Altered anatomy was present in 2 (6.25%). The indication for drainage was biliary obstruction from pancreatic cancer in 26 patients (84.5%), cholangiocarcinoma in 3 (9.4%), and ampullary mass in 3 (9.4%). The procedure was performed mostly in an outpatient setting (n = 19, 59.38%). The clinical success rate was 92.3% [bilirubin: 14.1 (SD: 8.9) preprocedure vs 4.9 (SD: 1.1) postprocedure; P = 0.0001]. There was one early adverse event of a perforation, which was closed endoscopically and drained percutaneously. Delayed adverse events included food impaction of the stent (n = 1), which was resolved with a repeat procedure and insertion of a double pigtail stent. CONCLUSION: This study demonstrates the feasibility of EUS-BD drainage using smaller caliber 6 or 8 mm lumen-apposing metal stent to relieve malignant distal bile duct obstruction in patients who fail conventional ERCP.

14.
Nature ; 562(7728): 600-604, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30323285

RESUMO

Mechanisms that integrate the metabolic state of a cell with regulatory pathways are necessary to maintain cellular homeostasis. Endogenous, intrinsically reactive metabolites can form functional, covalent modifications on proteins without the aid of enzymes1,2, and regulate cellular functions such as metabolism3-5 and transcription6. An important 'sensor' protein that captures specific metabolic information and transforms it into an appropriate response is KEAP1, which contains reactive cysteine residues that collectively act as an electrophile sensor tuned to respond to reactive species resulting from endogenous and xenobiotic molecules. Covalent modification of KEAP1 results in reduced ubiquitination and the accumulation of NRF27,8, which then initiates the transcription of cytoprotective genes at antioxidant-response element loci. Here we identify a small-molecule inhibitor of the glycolytic enzyme PGK1, and reveal a direct link between glycolysis and NRF2 signalling. Inhibition of PGK1 results in accumulation of the reactive metabolite methylglyoxal, which selectively modifies KEAP1 to form a methylimidazole crosslink between proximal cysteine and arginine residues (MICA). This posttranslational modification results in the dimerization of KEAP1, the accumulation of NRF2 and activation of the NRF2 transcriptional program. These results demonstrate the existence of direct inter-pathway communication between glycolysis and the KEAP1-NRF2 transcriptional axis, provide insight into the metabolic regulation of the cellular stress response, and suggest a therapeutic strategy for controlling the cytoprotective antioxidant response in several human diseases.


Assuntos
Glicólise , Proteína 1 Associada a ECH Semelhante a Kelch/química , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Processamento de Proteína Pós-Traducional , Transdução de Sinais , Animais , Elementos de Resposta Antioxidante/genética , Arginina/química , Arginina/metabolismo , Linhagem Celular , Cisteína/química , Cisteína/metabolismo , Citoproteção , Glicólise/efeitos dos fármacos , Humanos , Imidazóis/química , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fator 2 Relacionado a NF-E2/agonistas , Fosfoglicerato Quinase/antagonistas & inibidores , Multimerização Proteica , Aldeído Pirúvico/química , Aldeído Pirúvico/metabolismo , Aldeído Pirúvico/farmacologia , Transdução de Sinais/efeitos dos fármacos , Estresse Fisiológico/genética , Transcrição Gênica , Ubiquitinação
15.
Nucleic Acids Res ; 50(8): 4450-4463, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35394046

RESUMO

Mediator activates RNA polymerase II (Pol II) function during transcription, but it remains unclear whether Mediator is able to travel with Pol II and regulate Pol II transcription beyond the initiation and early elongation steps. By using in vitro and in vivo transcription recycling assays, we find that human Mediator 1 (MED1), when phosphorylated at the mammal-specific threonine 1032 by cyclin-dependent kinase 9 (CDK9), dynamically moves along with Pol II throughout the transcribed genes to drive Pol II recycling after the initial round of transcription. Mechanistically, MED31 mediates the recycling of phosphorylated MED1 and Pol II, enhancing mRNA output during the transcription recycling process. Importantly, MED1 phosphorylation increases during prostate cancer progression to the lethal phase, and pharmacological inhibition of CDK9 decreases prostate tumor growth by decreasing MED1 phosphorylation and Pol II recycling. Our results reveal a novel role of MED1 in Pol II transcription and identify phosphorylated MED1 as a targetable driver of dysregulated Pol II recycling in cancer.


Assuntos
Neoplasias , RNA Polimerase II , Animais , Humanos , Masculino , Mamíferos/genética , Complexo Mediador/metabolismo , Subunidade 1 do Complexo Mediador/genética , Neoplasias/genética , Fosforilação , RNA Polimerase II/metabolismo , Transcrição Gênica
16.
Artigo em Inglês | MEDLINE | ID: mdl-38719073

RESUMO

BACKGROUND: The prevalence of reverse total shoulder arthroplasty (rTSA) has grown rapidly. As indications for the procedure expand, the proportion of patients who have satisfactory outcomes after rTSA has not been well defined. This systematic literature review explores overall patient satisfaction after rTSA and defines patient satisfaction based on indication for surgery. METHODS: A literature search was performed for studies describing patient satisfaction after rTSA in accordance with Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Papers were included if they investigated patient satisfaction after rTSA at a minimum of 2-year follow-up. Data were collected on patient demographics, including age, gender, and body mass index. Follow-up duration, indication for surgery, and patient reported outcome measures relating to patient satisfaction were also recorded. RESULTS: There were a total of 5234 patients and 5288 shoulders from the 45 included studies. The overall study population was 61.2% female and the average age was 71.1 years (range 23-99). Satisfaction results were recorded at final follow-up, with average follow-up of 49.1 months (range 24-228). Overall patient satisfaction ranged from 77.7% to 87.8%, depending on patient satisfaction patient reported outcome measures. When stratified by diagnosis, patients with a diagnosis of glenohumeral osteoarthritis (GHOA) rated better satisfaction on all metrics when compared to patients with a diagnosis of cuff tear arthropathy or massive rotator cuff tear. CONCLUSION: This systematic review demonstrated that patients who undergo rTSA for either GHOA, cuff tear arthropathy, or massive rotator cuff tear are generally satisfied with their procedure, with the rate of satisfaction highest in GHOA. Focusing on patient satisfaction may provide the best overall assessment of health care quality in a very understandable and tangible form. Overall satisfaction rate is valuable information for patient education and can be utilized as part of effective surgical counseling.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38604401

RESUMO

BACKGROUND: As the number of total shoulder arthroplasty (TSA) procedures increases, there is a growing interest in improving patient outcomes, limiting costs, and optimizing efficiency. One approach has been to transition these surgeries to an outpatient setting. Therefore, the purpose of this study was to conduct an age-stratified analysis comparing the 90-day postoperative outcomes of primary TSA in the same-day discharge (SDD) and inpatient (IP) settings with a specific focus on the super-elderly. METHODS: This retrospective study included all patients who underwent primary anatomic or reverse TSA between January 2018 and December 2021 in ambulatory and IP settings. The outcome measures included length of stay (LOS), complications, hospital charges, emergency department (ED utilization), readmissions, and reoperations within 90 days following TSA. Patients with LOS ≤8 hours were considered as SDD, and those with LOS >8 hours were considered as IP. P < .05 was considered statistically significant. RESULTS: There were 121 and 174 procedures performed in SDD and IP settings, respectively. There were no differences in comorbidity indices between the SDD and IP groups (American Society of Anesthesiologists score P = .12, Elixhauser Comorbidity Index P = .067). The SDD cohort was younger than the IP group (SDD 67.0 years vs. 73.0 IP years, P < .001), and the SDD group higher rate of intraoperative tranexamic acid use (P = .015) and lower estimated blood loss (P = .009). There were no differences in 90-day overall minor (P = .20) and major complications (P = 1.00), ED utilization (P = .63), readmission (P = .25), or reoperation (P = .51) between the SDD and IP groups. When stratified by age, there were no differences in overall major (P = .80) and minor (P = .36) complications among the groups. However, the LOS was directly correlated with increasing age (LOS = 8.4 hours in ≥65 to <75-year cohort vs. LOS = 25.9 hours in ≥80-year cohort; P < .001). There were no differences in hospital charges between SDD and IP primary TSA in all 3 age groups (P = .82). CONCLUSION: SDD TSA has a shorter LOS without increasing postoperative major and minor complications, ED encounters, readmissions, or reoperations. Older age was not associated with an increase in the complication profile or hospital charges even in the SDD setting, although it was associated with increased LOS in the IP group. These results suggest that TSA can be safely performed expeditiously in an outpatient setting.

18.
Artigo em Inglês | MEDLINE | ID: mdl-38631455

RESUMO

BACKGROUND: Glenoid bone loss in shoulder arthroplasty is a difficult problem that is prone to complications because of challenges with achieving glenoid component fixation and stability. The purpose of this study was to evaluate the outcomes of primary shoulder hemiarthroplasty for patients with severe glenoid medialization precluding placement of a glenoid component. METHODS: This was a retrospective case series evaluating patients who underwent shoulder hemiarthroplasty for severe glenoid erosion and medialization between 2010 and 2020. Patients were evaluated via chart review and phone survey to determine if there were any reoperations at final follow-up and to obtain Single Assessment Numeric Evaluation (SANE), American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), and Simple Shoulder Test (SST) scores. Preoperative and postoperative radiographs were evaluated and compared to determine glenoid morphology, version, medialization, acromiohumeral distance, and humeral offset. Final postoperative films were also evaluated for anterosuperior migration and signs of mechanical failure, including loosening or periprosthetic fracture. RESULTS: Overall, there were 28 patients during this period who underwent shoulder hemiarthroplasty for severe glenoid medialization. Eight patients were deceased at the time of the study, 2 were unable to complete surveys because of dementia, and 7 were lost to follow-up. The final cohort included 11 shoulders and 11 patients with a mean age of 71 ± 7.1 years and mean follow-up of 6.7 years (range 1.6-13.0 years). Mean postoperative SANE, ASES, and SST scores were 80.6 ± 17.6, 71.5 ± 29.3, and 7.6 ± 2.0, respectively. There were no reoperations or revision surgeries at final follow-up. Radiographic evaluation demonstrated severe glenoid medialization and decreased lateral humeral offset, which was unchanged postoperatively. There were 2 patients with signs of anterosuperior migration at final radiographic follow-up but no signs of implant failure. CONCLUSION: Shoulder hemiarthroplasty for severe medial glenoid bone loss provides modest clinical outcomes and low rates of reoperation at mid- to long-term follow-up and is an option worth considering in cases where placement of a glenoid component is challenging because of deficient bone stock and high risk for complications.

19.
Palliat Support Care ; : 1-9, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38389458

RESUMO

OBJECTIVES: Male rectal and anal cancer patients demonstrate high rates of sexual dysfunction. This pilot randomized controlled trial tested a psychoeducational intervention designed to improve psychosexual adjustment. METHODS: Rectal or anal cancer patients were randomized to a Sexual Health Intervention for Men (intervention) or to a referral and information control (control). The intervention included control activities plus 4 sexual health intervention sessions every 4-6 weeks and 3 brief telephone calls timed between these sessions. Assessments were completed pre-intervention (baseline) and 3 months (follow-up 1) and 8 months (follow-up 2) post-intervention. Differences were assessed with statistical significance and Cohen's d effect sizes (d = 0.2, small effect; d = 0.5, moderate effect; d = 0.8, large effect). RESULTS: Ninety subjects enrolled. Forty-three participants completed at least 1 follow-up assessment (intervention, n = 14; control n = 29). At follow-up 1, men in intervention, compared to control, improved on all domains of the International Index of Erectile Function (IIEF) (p < 0.001 to p < 0.05) and demonstrated large effects (d = 0.8 to d = 1.5). Similarly, at follow-up 2, changes in all domains of the IIEF except the orgasm domain were either statistically significant or marginally statistically significant (p = 0.01 to p = 0.08) and demonstrated moderate to large treatment effects for intervention versus control (d = 0.5 to d = 0.8). Men in the intervention, compared to control, demonstrated decreased sexual bother at follow-up 1 (p = 0.009, d = 1.1), while Self-Esteem and Relationship (SEAR) total scores and the SEAR sexual relationship subscale demonstrated moderate increases for intervention versus control (d = 0.4 to d = 0.6). SIGNIFICANCE OF RESULTS: This study provides initial evidence for combining a psychoeducational intervention with medical interventions to address sexual dysfunction following rectal and anal cancer. Trials register number: NCT00712751 (date of registration: 7/10/2008).

20.
Biochemistry ; 62(21): 3126-3133, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37884446

RESUMO

The protein PARK7 (also known as DJ-1) has been implicated in several diseases, with the most notable being Parkinson's disease. While several molecular and cellular roles have been ascribed to DJ-1, there is no real consensus on what its true cellular functions are and how the loss of DJ-1 function may contribute to the pathogenesis of Parkinson's disease. Recent reports have implicated DJ-1 in the detoxification of several reactive metabolites that are produced during glycolytic metabolism, with the most notable being the α-oxoaldehyde species methylglyoxal. While it is generally agreed that DJ-1 is able to metabolize methylglyoxal to lactate, the mechanism by which it does so is hotly debated with potential implications for cellular function. In this work, we provide definitive evidence that recombinant DJ-1 produced in human cells prevents the stable glycation of other proteins through the conversion of methylglyoxal or a related alkynyl dicarbonyl probe to their corresponding α-hydroxy carboxylic acid products. This protective action of DJ-1 does not require a physical interaction with a target protein, providing direct evidence for a glutathione-free glyoxalase and not a deglycase mechanism of methylglyoxal detoxification. Stereospecific liquid chromatography-mass spectrometry (LC-MS) measurements further uncovered the existence of nonenzymatic production of racemic lactate from MGO under physiological buffer conditions, whereas incubation with DJ-1 predominantly produces l-lactate. Collectively, these studies provide direct support for the stereospecific conversion of MGO to l-lactate by DJ-1 in solution with negligible or no contribution of direct protein deglycation.


Assuntos
Doença de Parkinson , Aldeído Pirúvico , Humanos , Aldeído Pirúvico/química , Aldeído Pirúvico/metabolismo , Doença de Parkinson/metabolismo , Óxido de Magnésio , Ácido Láctico , Proteína Desglicase DJ-1
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